This disclosure relates generally to aircraft system health monitoring for overheat and fire detection systems. More particularly, this disclosure relates to optical signal analysis of aircraft system health monitoring systems.
During operation of an aircraft, numerous on-board components and sub-systems are continuously or periodically monitored. Various methods for monitoring these components and sub-systems of the aircraft have been used. For example, sensors and/or transducers can be affixed to an aircraft at specific locations so as to produce signals indicative of various physical phenomena experienced at those specific locations. These signals can then be transmitted to an analyzer that interprets the signals received by the analyzer. These signals can be processed to generate parametric data that can be correlated to measurements of physical phenomena. Some of the specific locations where it would be desirable to affix a sensor and/or transducer might be locations that have harsh environments. For example, some such locations might expose any affixed sensor to high temperatures, high pressures, high levels of exposure to electromagnetic interference, etc.
In many of these harsh environment locations, optical transducers have found use. Optical sensors and/or transducers can produce optical signals indicative of various physical phenomena. For example, optical sensors and/or transducers can produce optical signals indicative of stress, strain, temperature, tilt, rotation, vibration, pressure, etc. Various sensors and/or transducers employ various types of technologies. For example, some sensors use Fabry-Pérot Interferometry (FPI), while others use fiber Bragg grating (FBG) technologies. Some of these technologies and techniques produce optical signals having a spectrum that is indicative of the measured parameter. Spectrum analysis and/or spectral measurement of such signals is performed to determine a measure of the physical phenomena causing the specific spectrum of the optical signal.